Solving a System of Equations: (x-4)(y-7)=0 and y-5/x+y-9=2
This article will guide you through the process of solving the system of equations:
(1) (x-4)(y-7) = 0 (2) y - 5/x + y - 9 = 2
Understanding the First Equation
The first equation, (x-4)(y-7) = 0, represents a product of two factors equaling zero. This means either (x-4) = 0 or (y-7) = 0, or both. Let's break down the possibilities:
- Case 1: x - 4 = 0 This leads to x = 4.
- Case 2: y - 7 = 0 This leads to y = 7.
Working with the Second Equation
The second equation, y - 5/x + y - 9 = 2, is more complex. To solve for x and y, we need to:
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Simplify the equation: Combine like terms and move the constant term to the right side: 2y - 5/x = 11
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Isolate y: Multiply both sides by x: 2xy - 5 = 11x
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Solve for y: Rearrange the equation to express y in terms of x: y = (11x + 5) / 2x
Combining the Solutions
Now, we need to combine the solutions we found from the first equation with the expression for y from the second equation:
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If x = 4: Substitute x = 4 into the expression for y: y = (11 * 4 + 5) / (2 * 4) = 49 / 8
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If y = 7: Substitute y = 7 into the expression for y: 7 = (11x + 5) / 2x 14x = 11x + 5 3x = 5 x = 5/3
Solutions
Therefore, the solutions to the system of equations are:
- x = 4, y = 49/8
- x = 5/3, y = 7
Verification
It's always a good idea to verify our solutions by plugging them back into the original equations:
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For (x = 4, y = 49/8): (4-4)(49/8-7) = 0 * 0 = 0 49/8 - 5/4 + 49/8 - 9 = 2
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For (x = 5/3, y = 7): (5/3 - 4)(7 - 7) = 0 * 0 = 0 7 - 5/(5/3) + 7 - 9 = 2
Conclusion
We successfully solved the system of equations using a combination of factoring, simplification, and substitution. The solutions (x = 4, y = 49/8) and (x = 5/3, y = 7) satisfy both equations in the system.